[pornel]

I personally like how it handles hundreds of tabs. No matter how many tabs I have open they remain usable size, and the compact UI theme is even more compact than Chrome.

Tab containers are useful for having multiple accounts on the same site (Gmail/Github), or isolating work or most secure sites from regular browsing. The containers are more light-weight and more general than Chrome profiles (and they don't depend on having external accounts).

Pinned tabs don't close on Command+W. It's a small thing, but I kept accidentally closing my pinned tabs in Chrome.

Chrome Dev Tools are hard to beat, although Fx is slowly catching up there, too. I don't mind launching Chrome just for web dev.

[scholia]

> No matter how many tabs I have open they remain usable size

They were! I think they've shrunk, though that might be an optical illusion... And I can't see a simple way to make them bigger (simple as in: not editing the css file).

[mythmon_]

There is a pref that controls the minimum width now (browser.tabs.tabMinWidth). The default changed from 100px to 76px in Firefox 57. You should be able to tweak this to change the minimum width.

[scholia]

Fantastic. Many many thanks.